Means for binding magnetic core structurs



Feb. 1, 1949. M. B. GROUT MEANS FOR BINDING MAGNETIC CORE STRUCTURES 2she ets sheet 1 Filed Sept. 11, 1944 Feb. 1, 1949. M. B. GROUT 2,460,639

' MEANS FOR BINDING MAGNETIC CORE STRUCTURES Filed Sept. 11, 1944 I 2sheet -sheet 2 Patented Feb. 1, 1 949 MEANS FOR BINDING MAGNETIC comaSTRUCTURES -Martin B. Grout, Chicago, IlL, 'assignor to JefiersonElectric Company, Bellwood, 111., a corporation of Illinois ApplicationSeptember 11, 1944,: Serial No. 553,616

. Claims.

This invention relates to a fixture for tight ening and securing a straparound a magnetic core structure. V a

Reference is made to copending application of Leopold Mauerer, SerialNo. 519,732, filed January 26, 1944, (Patent No. 2,431,950 granted Dec.2, 1947), for a disclosure of the particular type of core structure inwhich a strap may be advantageously used to clamp the various sectionsof the core structure together. In that application a U-shapedclampingstrap is used which cooperates at one end of the core structure with across bar or other like element in such a manner that the strap may betensioned to hold the abutting sections of the core in operativerelationship.

In the present invention it is contemplated that the ends of theU-shaped strap be threaded through a cross bar, then that the strap betensioned, and then that the ends which project ing of such characterthat the strap will interlock with a cooperating member so that thestrap will be maintained under tension even after the fixture isremoved.

Other objects are to provide a fixture of this general type which is ofcomparatively simple construction and operation. j

Various other objects, features and advantages will appear as thedescription proceeds.

With reference now to the drawing in which like numerals designate likeparts;

Fig. 1 is an elevation of a preferred embodiment of this invention as itis applied to a mag:

netic core structure, a changed position ofthe partsbeing shown inbroken lines;

Fig. 2 is an end view of Fig. 1; Fig. 3 is a section taken along line3-3 of Fig.

2; V Fig. 4 is a view of the bending tool; Fig. 5 is an end view of Fig.4;

Fig. 6 is atop view of Figs. 1 and 2; I Fig. 7 is a section taken alongline 1 of Fig. 1; and

(Cl. 153--1) I I pointed out in greater detail Fig. 8 is'a section takenalong line 8-8 of Fig 2.

The'reference' numeral l8 designates generally the' ji'gor fixture.As'shown in the figures, it is designed to cooperate with anelectromagnetic core structure, which here is shown as being made ina'pl'urality of sections, section I2 being a reactance core and sectionl3 being a transformer core; These two sections are held in closelyabutting relationship by means of a U-shaped strap M which is providedwith rockers i5 which bridge the joint between the two sections, andserve to apply lateral pressure to the laminations of each section toprevent spreading. This construction, and the advantages thereof are inthe copending application above referred to.

:As a means of securing the strap in position, and for maintaining itunder the proper tension, an end bar l6'is provided which overlies theedges of the laminations of the core section 12. This end bar I6 isapertured so that the ends of the strap i4 maybe threaded through thesame.

.The fixture l0 serves to draw up the strap and to bend 'overthe endsthereof so that the strap will be maintained under tension, the bentover ends being designated in Fig. 1 by the reference numerals 32 and33.

- The fixture comprises a body member I! which is provided withcylindrical bores 18 and 19, these bores being substantially alignedwith the ends in the central projecting member 20 so that thebody memberI! may be forced downwardly with respect to block 22 .as the screw istightened. The central projecting member 29 may also be provided with apin 24 which is adapted to fit into the aperture in the end bar it. Thusthe fixture It] may be properly centered with respect to the, corestructure ll. As herein shown, the pin 24 is co-axialwith the bore inwhich the screw 23 is received, although of course the pin m'ayoccupy'any suitable position in the projectmg member 29, or a plurality of pinsmay be used if desired. v

The block 22 carries clamping arms 25. and 26,

whic l i'jarei pivotally mountedon block 22 so that they may be broughtdown from the dotted line position shown in Fig. 1, into the solid lineposition, in which they engage the strap M. The strap is provided Withapertures 21 in which the ends of the clamping arms 25 and 26 arereceived. v

It will be seen that after the fixture ii! is centered with respect tothe core structure I I, the clamping arms 25 and 26 may be brought intoengagement with the strap M. Then as the screw 23 is tightened, the endbar lfi' will be-for'ced downwardly with respect to the strap, or thestrap will be drawn upwardly with respect tothe end bar. This relativemovement of the parts causes the core sections 82 and [3 to be pressedinto that tightly abutting relationship which is desirable for properoperation of the electromagnet device, and which also results in theends. of the strap being projected through the end bar I6 by anincrement which corresponds to the'extent of the tensioning action.

After the strap It has beentensionedto the proper degree, the ends-ofthe strap are bent over into the positions designated by the referencenumerals 32 and 33 so that this tension may" be maintained after thefixture i is removed. This is accomplished. by a tool 28 shown in Figs.4 and the tool comprising a plug 29' having: a rearwardly projectingedge 30 which is adapted: to engage the ends of the. strap. The tool isalso provided with a handle 3|.

In operation the plug 29 is-fitted into the borei8 so that the edge 30engages. the right side-of the end of the. strap, as the partsare'viewed in Fig. 1. wise direction will result in the bending overofthe strap into the position designated by the reference numeral 32*.

Rotation of the tool in a-countercloc'le- It will be observed that thebody member H is provided with partial sleeves 34' and 35 whichprojectfrom the front surface thereof; and are concentric with the bores l8 andI9; These sleeves extend through only asportion'or that-"1111 360, andthey serveas stops to li-niitthe motion of. the handle 3! of the tool.More'specifically,

they prevent inadvertent rotationof: the tool downwardly against thecentral portion of: the

and. bar I6 at the inception of the bending operation; and at theconclusion they prevent the rotation of the tool into engagementthestrap l4.

The operation of the device as a whole has been pointed out above indet'aill in connection" with the description of parts. It isisufiicientto point out that after the fixture l 0 is applied tothecorestructure I I, and after the strap whats been tensioned by tighteningthe screw 23;.the-toolv maybe inserted firstinbore l8 to bend over end1-12", and then into bore I9" tobend over: and 33.

After this is done; the screw 23*may be loosened-a bit so that theclamping arms 25and 26can' be dis engaged" from the strap l4,thereby'permitting" removal of the fixture l0.

It. is contemplated that'in-mass production or electromagnet unitsembodying" thi's strap construction, the screw 23 maybe engaged? andtightened'by a motor driven chuck; emboidying'an' adjustable slip clutchby means of which the: tension from the strap I4 may be automatically itwill be obvious that various modifications and changes may be madetherein without departing from the spirit of this invention. Theforegoing description and the drawings are deemed to be illustrativeonly, and the invention is limited only by the appended claims.-

I claim V 1. Apparatus for use in binding a sectional magnetic corestructure which includes a, U- shaped strap and a cooperating end bar,said aparat'ue comprising. a body member having a surface adapted torest on said core structure, a block slidably associated with said bodymember, s-trap interlocking means carried by said block, means forforcing said block away from said body member to tension said strap, andmeans" cooperating with said body member for deforming the ends of saidstrap while it is maintained under tension by said interlocking meansso" tl-iatsaid deformed: ends will cooperate with sainl end bar tomaintainthe parts in tensic'ried relationship after said apparatus is.removed;

2; Apparatus-for use inbinding electi'ofiiagnet corestructures which areprovided with U- shaped strap, and with anend bar through which thestrapextezids,.. said apparatus comprising means-tointerlock: with thestrap, means to draw upon said str ct y-interlocking. means with respectto the end bar so that the ends of said 's't'r'ap will be:projectedthrough said eiid bar, means providing a pair oispaced' apartbearings 7 adapted tobe-removably secured" to saidend bar sothat said.bearings are subs'tar'itially aligned with the projecting. ends of thesir-a rotating in one of said hearings end of said strap and for bend g'it 0 said. strapis maintainedund'ertension by said interlocking means. 7

Apparatus for usein binding a sectional magnetic core structure whichincludes a' U shapedstrap' and a cooperating end' bar; sai'd" 7 meanscomprising'a body member adaptedto be bore, a rotatableelementjournal'edin'" aidbore,

mounted on said? and bar, a second member slidably. associated-with saidbody member, strap engaging means molinted o'n saidsec'ond for movementinto and'lout of" engaging relationship was said strap; means, torshifting the spacial relationship betweensaid"secondmembe'r andsaid'body nieinberaga s 'he't'efisi'on or the strap,.ofie ennui-membersbeihgp'rovided With'a and. a strap. bending; member: roje' eccentrically'fronrsalid rotatable element an'd'adapted' to engage said strap at aoint between'an end thereof andsaidend bar; whereby rotation of."

said rotatable. element will cause an end oi" said" strap to be bent0vei;againstsaid bar;

4". Apparatus" fol" age in binding a" sectional magnetic core structurewhich includes a" U shaped" strap and a cooperating.- end bar; said out"of engaging?relatiiiiiship' W1 h' sa'id' str'an,

means" for shifting. the: spacial" relationship be tween said member:and." saidtfixture .a'gairrst the tension of the stra each beingdisposedinsubstantial"alignmentwith the end of saidU-shaped strap, and-atool having" two" bearings" in said: fixture.

position with an end of the strap for successively;

deforming first one end and then the other end of said strap while it ismaintained under tension so that said deformed ends will cooperate withsaid end bar to maintain the parts in tensioned relationship after saidfixture is removed.

5, Apparatus for use in binding a sectional magnetic core structureprovided with an end bar disposed along one surface of said corestructure and projecting beyond the sides thereof, said end bar beingprovided with apertures at its project ing ends, and a U-shaped strapencircling the other three surfaces of said core structure and havingits free ends projecting through said apertures comprising, a blockadapted to rest on said end bar, strap engaging means slidablyassociated with said block, means for shifting the spacial relationshipbetween said strap engaging means and said block to tension said strapand to cause the free ends thereof to be projected further through saidapertures, two bearings in said block which are spaced from each otherso as to be substantially aligned with said projecting ends of saidstrap when said block rests on'said end 6 bar, and means removablyjournaled in one of said bearings and having an eccentrically disposedprojection for engaging one of said projecting ends at a point close tothe surface of said end bar, whereby rotation of said means will cause adeformation of said projecting end at a point closely adjacent thesurface of said end bar whereby the parts of said sectional corestructure may be clamped together.

" MARTIN B. GROUT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 442,934 Ackerman Dec. 16, 1890612,074 Webb Oct. 11, 1898 1,277,305 Gerrard Aug. 27, 1918 1,598,799Blair et a1. Sept. 7, 1926 r 1,621,583 Hintz Mar. 22, 1927

